2,642 research outputs found

    Ionized Gas Motions and the Structure of Feedback Near a Forming Globular Cluster in NGC 5253

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    We observed Brackett α\alpha 4.05μ\mum emission towards the supernebula in NGC 5253 with NIRSPEC on Keck II in adaptive optics mode, NIRSPAO, to probe feedback from its exciting embedded super star cluster (SSC). NIRSPEC's Slit-Viewing Camera was simultaneously used to image the K-band continuum at \sim0.10.1'' resolution. We register the IR continuum with HST imaging, and find that the visible clusters are offset from the K-band peak, which coincides with the Br α\alpha peak of the supernebula and its associated molecular cloud. The spectra of the supernebula exhibit Br α\alpha emission with a strong, narrow core. The linewidths are 65-76 km s1^{-1}, FWHM, comparable to those around individual ultra-compact HII regions within our Galaxy. A weak, broad (FWHM\simeq150-175 km s1^{-1}) component is detected on the base of the line, which could trace a population of sources with high-velocity winds. The core velocity of Br α\alpha emission shifts by +13 km s1^{-1} from NE to SW across the supernebula, possibly indicating a bipolar outflow from an embedded object, or linked to a foreground redshifted gas filament. The results can be explained if the supernebula comprises thousands of ionized wind regions around individual massive stars, stalled in their expansion due to critical radiative cooling and unable to merge to drive a coherent cluster wind. Based on the absence of an outflow with large mass loss, we conclude that feedback is currently ineffective at dispersing gas, and the SSC retains enriched material out of which it may continue to form stars.Comment: 24 pages, 9 figure

    Barriers and facilitators to initial and continued attendance at community-based lifestyle programmes among families of overweight and obese children: a systematic review

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    The success of childhood weight management programmes relies on family engagement. While attendance offers many benefits including the support to make positive lifestyle changes, the majority of families referred to treatment decline. Moreover, for those who do attend, benefits are often compromised by high programme attrition. This systematic review investigated factors influencing attendance at community-based lifestyle programmes among families of over-weight or obese children. A narrative synthesis approach was used to allow for the inclusion of quantitative, qualitative and mixed-method study designs. Thirteen studies met the inclusion criteria. Results suggest that parents provided the impetus for programme initiation, and this was driven largely by a concern for their child's psychological health and wellbeing. More often than not, children went along without any real reason or interest in attending. Over the course of the programme, however, children's positive social experiences such as having fun and making friends fostered the desire to continue. The stigma surrounding excess weight and the denial of the issue amongst some parents presented barriers to enrolment and warrant further study. This study provides practical recommendations to guide future policy makers, programme delivery teams and researchers in developing strategies to boost recruitment and minimise attrition

    Predictors and outcomes of crossover to surgery from physical therapy for meniscal tear and osteoarthritis a randomized trial comparing physical therapy and surgery

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    BACKGROUND: Arthroscopic partial meniscectomy (APM) combined with physical therapy (PT) have yielded pain relief similar to that provided by PT alone in randomized trials of subjects with a degenerative meniscal tear. However, many patients randomized to PT received APM before assessment of the primary outcome. We sought to identify factors associated with crossing over to APM and to compare pain relief between patients who had crossed over to APM and those who had been randomized to APM. METHODS: We used data from the MeTeOR (Meniscal Tear in Osteoarthritis Research) Trial of APM with PT versus PT alone in subjects ≥45 years old who had mild-to-moderate osteoarthritis and a degenerative meniscal tear. We assessed independent predictors of crossover to APM among those randomized to PT. We also compared pain relief at 6 months among those randomized to PT who crossed over to APM, those who did not cross over, and those originally randomized to APM. RESULTS: One hundred and sixty-four subjects were randomized to and received APM and 177 were randomized to PT, of whom 48 (27%) crossed over to receive APM in the first 140 days after randomization. In multivariate analyses, factors associated with a higher likelihood of crossing over to APM among those who had originally been randomized to PT included a baseline Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain Score of ≥40 (risk ratio [RR] = 1.99; 95% confidence interval [CI] = 1.00, 3.93) and symptom duration of <1 year (RR = 1.74; 95% CI = 0.98, 3.08). Eighty-one percent of subjects who crossed over to APM and 82% of those randomized to APM had an improvement of ≥10 points in their pain score at 6 months, as did 73% of those who were randomized to and received only PT. CONCLUSIONS: Subjects who crossed over to APM had presented with a shorter symptom duration and greater baseline pain than those who did not cross over from PT. Subjects who crossed over had rates of surgical success similar to those of the patients who had been randomized to surgery. Our findings also suggest that an initial course of rigorous PT prior to APM may not compromise surgical outcome. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence

    Associations Between Jump Performance and Asymmetries with 30-m Sprint Completion Time

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    Asymmetries of the lower body during jumping have been examined as a method to predict risk for injury and guide training program development. Studies have primarily focused on how these asymmetries affect jump performance, but none have examined this in Division I track athletes nor how these are related to sprint performance. PURPOSE: To examine the relationship between jump performance and asymmetries of the vertical and broad jumps with 30-m sprint completion times. METHODS: Twenty-five Division I Track and Field athletes (12 sprinters and 13 non-sprinters) (height = 177.21 ± 10.43 cm; weight = 78.67 ± 24.15 kg) participated in this study. These subjects performed two trials of both the vertical jump (VJ) with their hands on their hips while standing on force platforms. Subjects also performed two trials of the broad jump (BJ) while standing on force platforms and the distance of the BJ was measured using a 100-m tape measure. Following the jump tests, subjects performed two trials of 30-m sprints in which time was recorded using timing gates and the trial with the shortest completion time was used for analysis. Force data from the VJ was used to determine jump height and inter-limb asymmetries and the trial with the greatest jump height was used for analysis. Force data from the BJ was used to determine inter-limb asymmetries from each trial and the trial with the greatest jump distance was used for analysis. Asymmetries were calculated with the symmetry index equation [(high value-low value)/total*100]. Spearman rank correlations were then conducted to determine if the jump performance and asymmetries were associated with sprint completion times. Significance was set at an alpha level of 0.05. RESULTS: Spearman rank correlations determined that both the VJ and BJ were negatively associated with 30-m sprint completion time (rs= -0.644 p=0.001 and rs=-0.563 p=0.003, respectively). Additionally, both the VJ height and BJ distance were positively correlated (rs=0.643 p=0.001). The VJ and BJ asymmetries were not significantly correlated with 30-m sprint performance (p\u3e0.05) nor were they correlated with either the VJ height or BJ distance. CONCLUSION: The findings of study indicate that coaches may want to monitor jump performance as it is related to sprint performance. On the other hand, the asymmetries measured were not associated with jump or sprint performance and this may be due to the sample as they were highly trained individuals with low levels of asymmetries during both jumps

    Happy Soldiers are Highest Performers

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    17 USC 105 interim-entered record; under review.The article of record as published may be found at: https://doi.org/10.1007/s10902-021-00441-xWe examined the prediction of affective well-being to work performance in the United States Army. We found that high positive affect (PA), low negative affect (NA), and high optimism predicted awards for performance and heroism in a sample of 908,096 U.S. Army soldiers (mean age 29.60 years old, SD = 9.16 years; with over 1⁄4 of a million ethnic minor- ities and over 150,000 women). Baseline high PA, low NA, and high optimism predicted awards over a four-year follow up window, in which 114,443 soldiers (12.60%) received an award. Each well-being variable predicted future awards for both women and men, for enlisted soldiers as well as officers, for several ethnicities, for varying levels of education, and controlling for a number of other potential explanatory variables. The effects of high positive and low negative affect were additive, with each predicting significantly beyond the other. Comparing the soldiers highest vs. lowest in well-being predicted an almost four- fold greater award recognition in the high group. Awards were predicted by both high and low arousal positive emotions, as well as low sadness and low anger. The relations between PA, NA, and optimism with award attainment were curvilinear, with the greatest difference in award attainment occurring between low and moderate levels of affective well-being, with little effect between moderate and high well-being.Identified in text as U.S. Government work
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